Pass notes No 2,731: Tutankhamun

Tutankhamun was born with a compromised immune system. Photograph: Martin Godwin

The following correction was printed in the Guardian's Corrections and clarifications column, Monday 22 February 2010

Tutankhamun's gold death mask was said to be inlaid with lapis lazuli when the reality was blue glass

Born: Sometime in 1342 BC.

Appearance: Good for his age.

I know him! Egyptian pharaoh from nine to 19, mummified pharaoh thereafter. Gold deathmask, lapis lazuli inlay, beautiful work. Inspiration for Steve Martin's finest musical comp­osition, the 1978 single King Tut. The breadth of your knowledge astounds. But do you know how he died?

Theories have abounded ever since intrepid, if hamfisted, explorer Howard Carter uncovered/desecrated the tomb in 1922 – murder by a rival, a chariot accident, wild animal attack, you name it. Which was it in the end? None of the above. What killed him was – wait for it – incest.

No! Yes. Well, that and a touch of ­plasmodium falciparum.

Explain. The battery of funky new tests run on him by the Egyptian Supreme Council of Antiquities has shown that, as was the wont of Ancient Egypt's ­royals, the pharaoh Akhenaten married his sister. Tutankhamun was the fatally weakened product of their union.

So unlike the homelife of our own dear queen. Quite. Their son had a bone disease, club foot and a com­promised immune system. He was also infected with the malarial parasite P. falciparum, and all that, plus a fracture from a fall, combined to kill him.

Instead of Dallas. I see. Anyway – the young pharaoh would have been ­unable to walk without support, which explains the 130 walking sticks found in the tomb with him. Tests on other remains also show that he himself was the father of two stillborn daughters.

The sins of the mothers and fathers, eh? Well, they wouldn't have seen it as a sin, that's your Judeo-Christian ­heritage retroactively talking, but yes, I take your point. These things do tend to take a while to work their way out.